Overview

What's more satisfying that an obscure puzzle lock? How about one that involves chess pieces and a remotely actuated cash drawer that opens as if by magic? That's awesome, let's build it!!

How It Works

This project uses an RFM69HCW Packet Radio Feather M0 paired with the PN532 NFC/RFID breakout board secreted under a chess board to read RFID tags hidden in the bases of the pieces. (These micro NFC/RFID NTAG tags are seriously tiny!)

When the correct pair of pieces are placed on the designated board spaces, the Feather board hidden inside the chess board sends an unlock message to the receiving Feather inside the cash drawer case that is paired with a Motor FeatherWing to drive a linear actuator, thus opening the drawer to reveal more clues. Amazing!

Here's the stream of John Park's Workshop LIVE if you'd like to see a more in depth tour of the build and operation.

Parts, Tools, & Materials

You'll need the parts listed in the section below, plus:

  • Chess board with storage space underneath to hide parts, such as a folding board, or one with internal piece drawers
  • Chess pieces with felt stickers on the bottoms (or get some felt stickers to add)
  • Two 1.5K ohm through hole resistors
  • Hook up wire
  • Trunk or drawer to open
  • Linear actuator, such as this one
  • Mounting hardware and fasteners, including clevis brackets for the actuator, or you can 3D print your own
  • Wire strippers
  • Soldering iron, solder
1 x RFID / NFC SMART RING - NTAG213
Optional operator's secret reset ring, choose your size
1 x 12V 5A SWITCHING POWER SUPPLY
12V motor power supply
2 x 5V 2.4A SWITCHING POWER SUPPLY WITH 20AWG MICROUSB CABLE
Optional Feather power supplies/battery chargers
Last updated on 2017-08-25 at 03.15.19 PM Published on 2017-08-25 at 04.40.15 PM